1. Field of the Invention
The invention concerns a flat structure made of sheet metal, foil or layers of foil for use as heat shields such as those used for between the muffler of a motor vehicle and other adjacent parts.
2. Description of Prior Art
German patent 9,103,864 discloses a heat shield of the general type which is the subject of the present invention. It describes a mat consisting of several layers of shaped foil, where these foil layers are arranged in parallel and at a spacing relative to each other. The layers are attached to a sheet metal part with appropriate fastening devices in such a way as to form a heat shield. With this known mat, each layer of the foil is deformed to prevent direct surface contact with each adjacent layer. The degree of thermal insulation of such a mat is greatly impaired, however, because due to the deformation of all mats, incident radiant heat is reflected repeatedly on the deformations, and the foil layers heat up due to transverse reflections, so that the resulting degree of thermal insulation is relatively unfavorable. Furthermore, it is regarded as a disadvantage that several mat layers must be used to achieve such an insulation effect.